The present invention relates to an air-bag and more particularly relates to an air-bag in the form of an inflatable curtain for use in a motor vehicle.
It has been proposed to provide motor vehicles with many different types of air-bag, in order to provide protection for the occupants of the vehicle in case various types of accident should occur.
To provide protection for an occupant of a vehicle in the case of a side impact or roll-over situation, it has been proposed to provide an air-bag which is in the form of an inflatable curtain. An air-bag of this type, when inflated, extends from the roof-line of the vehicle above the side doors or the side windows of the vehicle, downwardly to form a “curtain” extending across the window opening in the door or the windows on the side of the vehicle. The air-bag is provided to reduce the risk that the head or a limb of an occupant of the vehicle will be ejected through the windows of the vehicle during a side impact or roll-over situation.
In a side impact situation, it is necessary for an air-bag of this type to be inflated extremely swiftly, with inflation preferably being completed in less than 20 milliseconds. If it takes longer than this to inflate the air-bag, another vehicle or object impacting the side of the vehicle, may penetrate deeply into the cabin of the vehicle leading to an increased likelihood of injury of an occupant of the vehicle.
Because the air-bag of this type has to be inflated in a very short period of time following detection of a side impact, gas must flow, from the associated gas generator, into the air-bag at a very high rate. The inlet area of an inflatable curtain is therefore subjected to very high forces from the aggressive flow of gas during inflation of the inflatable curtain, especially during the initial stages of inflation.
It has been found that on some occasions the air-bag may rupture in the area of the gas inlet during inflation. The present invention seeks to provide an improved air-bag which reduces the likelihood of such ruptures.